Which fish is known as living fossil :-

Options

A. Chimaera
B. Latimaria
C. Pristis
D. Harpodon

Answer

**Step-by-Step Solution:**

1. **Understand the Question**: The question asks for a specific type of fish known as a "living fossil." This term refers to species that have remained relatively unchanged over long periods of geological time.

2. **Evaluate the Options**:
- **Option 1: Caimera**: This is a type of cartilaginous fish. While it is an interesting species, it is not classified as a living fossil.
- **Option 2: Latimeria**: This is the correct answer. Latimeria, commonly known as coelacanth, is often referred to as a living fossil because it was thought to be extinct for millions of years until it was rediscovered in 1938.
- **Option 3: Pristis**: This refers to a genus of sawfish, which are not considered living fossils.
- **Option 4: Harpadon**: This is a type of bony fish and does not fit the criteria for being a living fossil.

3. **Conclusion**: After evaluating all the options, the only fish that is known as a living fossil is **Latimeria** (option 2).

**Final Answer**: Latimeria

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